From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C28C3C64EBC for ; Thu, 4 Oct 2018 13:13:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70BAE2084D for ; Thu, 4 Oct 2018 13:13:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="K57Zm2OQ"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="UlQrDhjc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 70BAE2084D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727644AbeJDUGl (ORCPT ); Thu, 4 Oct 2018 16:06:41 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:45046 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727336AbeJDUGk (ORCPT ); Thu, 4 Oct 2018 16:06:40 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 3444260C88; Thu, 4 Oct 2018 13:13:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1538658805; bh=2X7XgT20bFpxJexb2oDBZnVE67sQXoE86PKVwfiTfKM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=K57Zm2OQwapVg3eS6d06z3RQCdtpa1YRJJHANcJPfG8cWOYt32qb4LTflooJQp2XK HbN2MbI/8vLAOOTIRlyX88TkgO633PE9KUW3CbbIURrzZ9QDS+OKvwedPi50/LotOV 5QnyK/F1Q8x3YBVUCAuxWwEDqX2rMz1WifoAqhcM= Received: from [10.252.220.101] (blr-c-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.19.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: vbadigan@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 3B4FD60C86; Thu, 4 Oct 2018 13:13:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1538658804; bh=2X7XgT20bFpxJexb2oDBZnVE67sQXoE86PKVwfiTfKM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=UlQrDhjcfzXKLoKYgZlaObs0qWToIWLClx2m2ogVvGha/WaXvhsGiWV0szCJY43qu 8TixF7/FvsuzFaNqc+XkdHo9NecfDzBMg4C1WAgt7qbxpCuVaSmil/lihrMMhYx6gl JsxmvhiHxxQa9ibhJuNEHKvKN2fyUt+PCbo9lUvI= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3B4FD60C86 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vbadigan@codeaurora.org Subject: Re: [PATCH V2 2/3] dt-bindings: mmc: sdhci-msm: Add entries for passing load values To: Evan Green Cc: adrian.hunter@intel.com, Ulf Hansson , robh+dt@kernel.org, linux-mmc@vger.kernel.org, asutoshd@codeaurora.org, riteshh@codeaurora.org, stummala@codeaurora.org, sayali , Doug Anderson , vviswana@codeaurora.org, mark.rutland@arm.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <1537424558-17989-1-git-send-email-vbadigan@codeaurora.org> <1537424558-17989-3-git-send-email-vbadigan@codeaurora.org> <8f26b82c-b966-11d3-4fb6-0137a0a8cd4a@codeaurora.org> From: Veerabhadrarao Badiganti Message-ID: <3bbb160d-6963-ba97-710f-41247cff53b6@codeaurora.org> Date: Thu, 4 Oct 2018 18:43:17 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/22/2018 1:36 AM, Evan Green wrote: > On Fri, Sep 21, 2018 at 3:32 AM Veerabhadrarao Badiganti > wrote: >> Hi Evan, >> >> >> On 9/21/2018 5:45 AM, Evan Green wrote: >>> On Wed, Sep 19, 2018 at 11:24 PM Veerabhadrarao Badiganti >>> wrote: >>>> From: Vijay Viswanath >>>> >>>> The load a particular sdhc controller should request from a regulator >>>> is device specific and hence each device should individually vote for >>>> the required load. >>>> >>>> Signed-off-by: Vijay Viswanath >>>> Signed-off-by: Veerabhadrarao Badiganti >>>> --- >>>> Documentation/devicetree/bindings/mmc/sdhci-msm.txt | 6 ++++++ >>>> 1 file changed, 6 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt >>>> index 502b3b8..3720385 100644 >>>> --- a/Documentation/devicetree/bindings/mmc/sdhci-msm.txt >>>> +++ b/Documentation/devicetree/bindings/mmc/sdhci-msm.txt >>>> @@ -26,6 +26,11 @@ Required properties: >>>> "cal" - reference clock for RCLK delay calibration (optional) >>>> "sleep" - sleep clock for RCLK delay calibration (optional) >>>> >>>> +Optional properties: >>>> +- qcom,-current-level-microamp - specifies load levels for supply during BUS_ON and >>>> + BUS_OFF states in power irq. Should be specified in >>>> + pairs (lpm, hpm), for BUS_OFF and BUS_ON respectively. >>>> + Units uA. >>>> Example: >>>> >>>> sdhc_1: sdhci@f9824900 { >>>> @@ -37,6 +42,7 @@ Example: >>>> >>>> vmmc-supply = <&pm8941_l20>; >>>> vqmmc-supply = <&pm8941_s3>; >>>> + qcom,vqmmc-current-level-microamp = <200 22000>; >>>> >>>> pinctrl-names = "default"; >>>> pinctrl-0 = <&sdc1_clk &sdc1_cmd &sdc1_data>; >>>> -- >>>> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project >>>> >>> Aren't the regulator load levels pretty coarse? Would it be safe to >>> say that pretty much all sd/mmc devices need the high powered mode, or >>> are there really some devices that can get by with LPM all the time? >>> -Evan >> The load levels here are min and max supported by the regulator. To >> cover all devices >> we do set it to max load. We can't make any assumptions on this, as >> peak current may vary >> from device to device. > Hi Veera, > If it were up to me, I would just assume all devices need high power > mode for BUS_ON and low power mode for BUS_OFF, and skip adding this > binding until you actually came up with a device that needed lower > power mode for BUS_ON, or high power mode for BUS_OFF (when would that > be, anyway?) Are there any actual use cases you've seen that need > different values in here? > -Evan Hi Evan, With the present implementation if these load values are not supplied in dt, its not setting any load at all. Without setting  load, I'm observing CRC/timeout/tuning errors. I can update the code to fallback to default values when these are not supplied in dt, but these values will be different from SD card and eMMC devices. So, this dt binding is needed. Thanks Veera